The present invention relates to a fixing device, and more specifically relates to a fixing device for applying pressure and heat to a sheet with toner attached to one surface thereof so as to melt the toner and thereby fix an image onto the sheet.
The present invention also relates to a manufacturing method for component members of such a fixing device.
The present invention further relates to an image forming apparatus having such a fixing device.
This kind of fixing device includes two members which are put in pressure contact with each other so as to form a nip section for fixation, and a heating source which heats at least one of the two members, in which sheets (e.g., paper) with toner attached to one surface thereof are conveyed through the nip section, so that the toner is melted through application of pressure and heat, and thereby an image is fixed to the sheets.
In the general fixing device, the two members have a smooth surface (with arithmetic average roughness Ra being 0.05 μm or less) which is made of fluorine-based resin such as PTFE (polytetrafluoroethylene) in order to enhance releasability of toner and paper powder.
It has conventionally been proposed to use fluorine-based resin containing carbon black (content ratio of fluorine-based resin is 95% or more) for the surface layer of belts used for forming the nip section (see e.g., JP 2003-5555 A). This prevents fixing belts from being charged and thereby prevents generation of electrostatic offset and the like.